U.S. patent number 7,122,024 [Application Number 10/603,008] was granted by the patent office on 2006-10-17 for open-type disposable wearing article having bifurcated stretchable zones.
Invention is credited to Yoshitaka Mishima, N/A, Kaiyo Nakajima, Tomoko Sugito.
United States Patent |
7,122,024 |
Nakajima , et al. |
October 17, 2006 |
**Please see images for:
( Certificate of Correction ) ** |
Open-type disposable wearing article having bifurcated stretchable
zones
Abstract
An open-type disposable wearing article composed of a front
waist region, a rear waist region and a crotch region. These
regions are all elastically stretchable. The article includes first
and second stretchable zones respectively bifurcated at a
transverse middle of the crotch region so as to extend to lateral
zones of the front and rear waist regions, respectively, and third
stretchable zones defined by zones other than the first and second
stretchable zones. The first and second stretchable zones exhibit a
stretch stress higher than a stretch stress of the third
stretchable zones. Loop members are provided to the second
stretchable zone in the lateral zones of the rear waist region and
hook members are provided to the first stretchable zone in the
lateral zones of the front waist region.
Inventors: |
Nakajima; Kaiyo, N/A
(Kagawa-ken, JP), Mishima; Yoshitaka, N/A
(Kagawa-ken, JP), Sugito; Tomoko, N/A
(Kagawa-ken, JP) |
Family
ID: |
29717567 |
Appl.
No.: |
10/603,008 |
Filed: |
June 24, 2003 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20040006326 A1 |
Jan 8, 2004 |
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Foreign Application Priority Data
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Jun 24, 2002 [JP] |
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2002-183415 |
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Current U.S.
Class: |
604/385.25;
604/391; 604/386; 604/385.24; 604/385.01 |
Current CPC
Class: |
A61F
13/49019 (20130101); A61F 13/5633 (20130101) |
Current International
Class: |
A61F
13/475 (20060101); A61F 13/62 (20060101); A61F
13/49 (20060101) |
Field of
Search: |
;604/385.01,385.22,391,385.24-385.25 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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1 201 212 |
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May 2002 |
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EP |
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2 282 522 |
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Apr 1995 |
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GB |
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2001-8968 |
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Jan 2001 |
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JP |
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WO 97 43994 |
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Nov 1997 |
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WO |
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Other References
Ciullo, Peter and Norman Hewitt. The Rubber Formulary. Norwich:
Noyes Publications, 1999, p. 60. cited by examiner .
Koshal, Dal. ed. Manufacturing Engineer's Reference Book. London:
Butterworth-Heinemann, 1993, p. 1/75. cited by examiner.
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Primary Examiner: Zalukaeva; Tatyana
Assistant Examiner: Gibson; Keshia
Attorney, Agent or Firm: Butzel Long
Claims
What is claimed is:
1. An open-type disposable wearing article comprising: an
elastically stretchable front waist region; an elastically
stretchable rear waist region; an elastically stretchable crotch
region extending between said front waist region and said rear
waist region and, said front and rear waist regions being
connectable with each other in opposite lateral zones thereof; a
first stretchable zone bifurcated at a transverse middle of said
crotch region so as to extend in two laterally separated portions
to said opposite lateral zones of said front waist region, said
first stretchable zone having a substantially uniform tensile
stress; a second stretchable zone bifurcated at said transverse
middle of said crotch region so as to extend in two laterally
separated portions to said opposite lateral zones of said rear
waist region, said second stretchable zone having a substantially
uniform tensile stress; and third stretchable zones defined by
zones other than said first and second stretchable zones, including
extending between the two laterally separated portions of each of
the first stretchable zone and the second stretchable zone and
along lateral side portions of at least the crotch region, a
tensile stress of said first and second stretchable zones being
higher than a tensile stress of said third stretchable zones; first
engageable means for connecting said front and rear waist regions
with each other, said first engageable means being provided in said
second stretchable zone in said opposite lateral zones of said rear
waist region; first receiving means releasably engageable with said
first engageable means, said first receiving means being provided
in said first stretchable zone in said opposite lateral zones; and
second engageable means for connecting said front and rear waist
regions to one another are provided in said third stretchable zones
lying in said opposite lateral zones of said rear waist region and
second receiving means for releasably engaging said second
engageable means are provided in said third stretchable zones lying
in said opposite lateral zones of said front waist region.
2. The wearing article according to claim 1, wherein said first
stretchable zone and said second stretchable zone are contiguous to
each other at said transverse middle of said crotch region.
3. The wearing article according to claim 1, wherein said first
engageable means comprise first loop members attached to an inner
surface of said rear waist region in said opposite lateral zones
thereof and said first receiving means comprise first hook members
attached to an outer surface of said front waist region in said
opposite lateral zones thereof.
4. The wearing article according to claim 1, wherein said second
engageable means comprise second hook members attached to said
inner surface of said rear waist region in said opposite lateral
zones thereof and said second receiving means comprise second loop
members attached to said outer surface of said front waist region
in said opposite lateral zones thereof.
5. The wearing article according to claim 1, wherein said first
stretchable zone lying in said opposite lateral zones of said front
waist region and said second stretchable zone lying in said
opposite lateral zones of said rear waist region are substantially
connected with each other as said first engageable means are
engaged with said first receiving means to put said wearing article
on the wearer's body.
6. The wearing article according to claim 1, wherein said wearing
article further comprises an elastically stretchable fibrous
nonwoven fabric having a basis weight thereof higher in said first
and second stretchable zones than in said third stretchable
zones.
7. The wearing article according to claim 1, wherein said first and
second stretchable zones have a tensile stress in a range of 0.25
30N when a width of said zones is 15 mm and said zones are
stretched by 15% and a tensile stress in a range of 0.6 50N when a
width of said zones is 15 mm and said zones are stretched by 40%
and wherein said third stretchable zone have a tensile stress in a
range of 0.17 20N when a width of said zone is 15 mm and said zone
is stretched by 15% and a tensile stress in a range of 0.4 33N when
a width of said zone is 15 mm and said zone is stretched by
40%.
8. The wearing article according to claim 1, wherein said wearing
article comprises a diaper cover used in combination with an
absorbent pad that is attached to a surface of said wearing article
that faces a wearer's body.
Description
BACKGROUND OF THE INVENTION
The present invention relates to an open-type disposable wearing
article.
Japanese Patent Application Publication No. 2001-8968A discloses an
open-type disposable diaper comprising a first inner sheet which
faces the wearer's body and is elastically stretchable in a
transverse direction of the diaper, a first outer sheet which faces
away from the wearer's body and is elastically stretchable in the
transverse direction and an absorbent pad which is interposed
between these first inner and outer sheets to configure a front
waist region, a rear waist region and a crotch region extending
between these waist regions wherein the crotch region is provided
on its transversely opposite sides with second inner and outer
sheets which are elastically stretchable not only in the transverse
direction but also in a longitudinal direction of the diaper.
In this known diaper, the elastically stretchable first inner and
outer sheets defining the front waist region, the rear waist
regions and the crotch region facilitate the diaper to be put on
the wearer's body because all of these regions are free from
formation of gathers. To put this diaper on the wearer's body, tape
fasteners attached to the opposite lateral zones of the rear waist
region may be anchored on the opposite lateral zones of the front
waist region so as to connect the front and rear waist regions with
each other.
In the case of the diaper disclosed in the above-cited Publication,
a contractile force of the first inner and outer sheets both being
elastically stretchable in the transverse direction certainly
serves to tighten the wearer's waist region in its circumferential
direction.
However, the first inner and outer sheets are substantially
non-stretchable in the longitudinal direction of the diaper and
therefore do not intend to pull the crotch region of the diaper
upward in the longitudinal direction. Consequently, it is
impossible for this known-diaper to keep the crotch region of the
diaper in close contact with the wearer's crotch region.
Furthermore, longitudinally opposite end zones of the second inner
and outer sheets are not connected together even after the diaper
has been put on the wearer's body, so these second inner and outer
sheets do not serve to tighten the wearer's legs in circumferential
direction. In other words, it is impossible to utilize a
contractile force of these second inner and outer sheets to tighten
the wearer's legs.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide an open-type
disposable wearing article improved so that the crotch region can
be kept in close contact with the wearer's crotch region and the
inguinal region as well as the waist region of the wearer cap be
properly tightened.
According to the present invention, there is an open-type
disposable wearing article having a front waist region, a rear
waist region and a crotch region extending between these waist
regions, all being elastically stretchable, the front and rear
waist regions being capable of connecting with each other along
opposite lateral zones thereof.
The wearing article has a first stretchable zone bifurcated at a
transverse middle of the crotch region so as to extend to the
opposite lateral zones of the front waist region, a second
stretchable zone bifurcated at the transverse middle of the crotch
region so as to extend to the opposite lateral zones of the rear
waist region and third stretchable zones defined by zones other
than the first and second stretchable zones. A stretch stress of
the first and second stretchable zones is higher than a stretch
stress of the third stretchable zones; and first engageable means
used to connect the front and rear waist regions with each other
are provided in the second stretchable zone in the opposite lateral
zones of the rear waist region and first receiving means releasably
engaged with the first engageable means are provided in the first
stretchable zone in the opposite lateral zones.
The present invention includes the following embodiments.
The first stretchable zone and the second stretchable zone are
contiguous to each other at the transverse middle of the crotch
region.
The first engageable means are first loop members attached to an
inner surface of the rear waist region in the opposite lateral
zones thereof and the first receiving means are first hook members
attached to an outer surface of the front waist region in the
opposite lateral zones thereof.
Second engageable means used to connect the front and rear waist
regions are provided in the third stretchable zones lying in the
opposite lateral zones of the rear waist region and second
receiving means releasably engaged with the second engageable means
are provided in the third stretchable zones lying in the opposite
lateral zones of the front waist region.
The second engageable means are second hook members attached to the
inner surface of the rear waist region in the opposite lateral
zones thereof and the second receiving means are second loop
members attached to the outer surface of the front waist region in
the opposite lateral zones thereof.
The first stretchable zone lying in the opposite lateral zones of
the front waist region and the second stretchable zone lying in the
opposite lateral zones of the rear waist region are substantially
connected with each other as the first engageable means are engaged
with the first receiving means to put the wearing article on the
wearer's body.
The wearing article is formed by a elastically stretchable fibrous
nonwoven fabric having a basis weight thereof higher in the first
and second stretchable zones than in the third stretchable
zones.
The first and second stretchable zones each exhibit a stretch
stress in a range of 0.25 30N when a width of the zones is 15 mm
and the zones are stretched by 15% and a stretch stress in a range
of 0.6 50N when a width of the zones is 15 mm and the zones are
stretched by 40% and the third stretchable zone exhibits a stretch
stress in a range of 0.17 20N when a width of the zone is 15 mm and
the zone is stretched by 15% and a stretch stress in a range of 0.4
33N when a width of the zone is 15 mm and the zone is stretched by
40%.
The wearing article is used as a diaper cover adapted to be used
together with an absorbent pad attached to a surface of the wearing
article facing a wearer's body.
The open-type disposable wearing article according to this
invention has advantageous effects that the first and second
stretchable zones are elastically contractible in the longitudinal,
i.e., the vertical direction, so the contractile force of these
stretchable zones normally intend to pull the crotch region of the
article upward. Such a feature ensures that the crotch region of
the article is kept in close contact with the wearer's crotch
region. The lateral zones of this article are defined by the third
stretchable zones exhibiting a stretch stress lower than those of
the first and second stretchable zones. This feature ensures that a
wearer's free movement is never restrained by the first and second
stretchable zones.
With the article in which the first and second stretchable zones
are contiguous to each other in the transverse middle of the crotch
region, the first and second stretchable zones cooperate to form an
annular configuration extending from the wearer's inguinal region
toward the wearer's waist region. This feature allows the
contractile force of the first and second stretchable zones to be
utilized to tighten the wearer's inguinal and waist regions.
With the article, the first engageable means must be engaged with
the receiving means to connect the first stretchable zone to the
second stretchable zone when the article is put on the wearer's
body. In other words, it is impossible to bring the loop members
attached to the lateral zones in the rear waist region in
engagement with any members or zones other than the hook members
when it is intentioned to put the article on the wearer's body. It
is thus ensured that the lateral zones of the front waist region
are connected to the lateral zones of the rear waist region always
at the proper positions thereof.
With article in which, in addition to the first engageable means
and the first receiving means to be anchored, there are formed in
the third stretchable zones with the second engageable means and
the second receiving means, the second engageable means are engaged
with the second receiving means and thereby the third stretchable
zones lying in the front and rear end zones are substantially
connected together. In this way, the wearer's waist region can be
tightened by the third stretchable zones in the circumferential
direction of the wearer's waist region.
With the article, the first engageable means may be engaged with
the first receiving means to place the second engageable means upon
the outer side of the second receiving means. In this way, the
second engageable means can be reliably engaged with the second
receiving means.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a partially cutaway plan view showing an example of the
disposable wearing article;
FIG. 2 is a sectional view taken along a line A--A in FIG. 1;
FIG. 3 is a sectional view taken along a line B--B in FIG. 1;
FIG. 4 is a sectional view taken along a line C--C in FIG. 1;
FIG. 5 is a perspective view showing the article of FIG. 1 as put
on a wearer's body;
FIG. 6 is a perspective view showing the article of FIG. 1 as put
on a wearer's body;
FIG. 7 is a partially cutaway plan view showing another example of
the disposable wearing article;
FIG. 8 is a sectional view taken along a line D--D in FIG. 7;
FIG. 9 is a sectional view taken along a line E--E in FIG. 7;
FIG. 10 is a sectional view taken along a line F--F in FIG. 7;
and
FIG. 11 is a perspective view showing the article of FIG. 7 as put
on a wearer's body.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Details of an open-type disposable wearing article according to the
present invention will be more fully understood from the
description given hereunder with reference to the accompanying
drawings.
FIG. 1 is a partially cutaway plan view showing an example of the
disposable wearing article, FIG. 2 is a sectional view taken along
a line A--A in FIG. 1, FIG. 3 is a sectional view taken along a
line B--B in FIG. 1 and FIG. 4 is a sectional view taken along a
line C--C in FIG. 1. In FIG. 1, a transverse direction is indicated
by an arrow X and a longitudinal direction is indicated by an arrow
Y. Expression "inner surfaces" of fibrous nonwoven fabric layers
m1, m2 as well as of top- and backsheets" refers to the surfaces
thereof facing wearer's body and expression "outer surfaces"
thereof refers to the surfaces thereof facing away from the
wearer's body.
An article 1A is composed, as viewed in its longitudinal direction,
of a front waist region 2, a rear waist region 4 and a crotch
region 3 extending between these two waist regions 2, 4 and has
front and rear end zones 5, 6 extending in the transverse direction
and lateral zones 7 extending in the longitudinal direction. In the
crotch region 3, the lateral zones 7 curve inward transversely of
the article 1A so as to describe circular arcs. The article 1A is
substantially hourglass-shaped as viewed in its developed state.
The article 1A is provided on its surface facing the wearer's body
with an absorbent pad P releasably attached thereto and this pad P
serves to absorb and to contain bodily discharges.
The article 1A comprises stretchable fibrous nonwoven fabric layers
m1, m2 placed upon each other. These nonwoven fabric layers m1, m2
are elastically stretchable in the transverse direction as well as
in the longitudinal direction not only in the front and rear waist
regions 2, 4 but also in the crotch region 3. In the article 1A,
the nonwoven fabric layer m1 lies on the side of the wearer's body
and the nonwoven fabric layer m2 lies on the side far from the
wearer's body. In the article 1A, the surfaces of these nonwoven
fabric layers m1, m2 opposed to each other are joined together
intermittently so that the elastic property intrinsic to these
nonwoven fabric layers m1, m2 might not be deteriorated due to
joining. Specifically, these nonwoven fabric layers m1, m2 may be
intermittently joined to each other in dot pattern, spiral pattern,
zigzag pattern or stripe pattern. The article 1A has a first
stretchable zone 8, a second stretchable zone 9 and third
stretchable zones 10a, 10b defined by zones other than the first
and second stretchable zones 8, 9.
The first stretchable zone 8 is bifurcated in a transverse middle
3a of the crotch region 3 so as to extend from the transverse
middle 3a to lateral zones 7a in the vicinity of the front end zone
5. The second stretchable zone 9 also is bifurcated in the
transverse middle 3a of the crotch region 3 so as to extend from
the transverse middle 3a to lateral zones 7b in the vicinity of the
rear end zone 6. In the transverse middle 3a of the crotch region
3, the first stretchable zone 8 and the second stretchable zone 9
are contiguous to each other and extend in the longitudinal
direction. These first and second stretchable zones 8, 9 extend
around the crotch region 3 substantially in X-shape.
The third stretchable zones 10a lie outside the first and second
stretchable zones 8, 9 as viewed in the longitudinal direction and
define the front and rear end zones 5, 6 of the article 1A. The
third stretchable zones 10b lie outside of the first and second
stretchable zones 8, 9 as viewed in the transverse direction and
define the lateral zones 7 of the article 1A.
In the first and second stretchable zones 8, 9, a stretchable
fibrous nonwoven fabric layer m3 is interposed between the nonwoven
fabric layers m1, m2. The nonwoven fabric layer m3 also is
elastically stretchable in the transverse direction as well as in
the longitudinal direction and intermittently joined to the
surfaces of the nonwoven fabric layers m1, m2 opposed to each
other. These nonwoven fabric layers m1, m2, m3 are intermittently
joined one to another under no tension. Thus the first and second
stretchable zones 8, 9 respectively comprise those three fibrous
nonwoven fabric layers m1, m2, m3 placed one upon another. The
third stretchable zones 10a, 10b, on the other hand, respectively
comprise those two fibrous nonwoven fabric layers m1, m2.
Consequently, the basis weight of the nonwoven fabric layer is
higher in the first and second stretchable zones 8, 9 than in the
third stretchable zones 10a, 10b and the stretch stress is higher
in the stretchable zones 8, 9 than in the third stretchable zones
10a, 10b.
The lateral zones 7a in the front waist region 2 are provided with
first hook members 11 attached thereto. The hook members 11 are
secured to an outer surface of the nonwoven fabric layer m2 in the
first stretchable zone 8. Similarly, the lateral zones 7b in the
rear waist region 4 are provided with first loop members 12
attached thereto. The loop members 12 are secured to an inner
surface of the nonwoven fabric layer m1 in the second stretchable
zone 9.
The pad P comprises a liquid-pervious topsheet 13 facing the
wearer's body, a liquid-impervious backsheet 14 facing away from
the wearer's body and a liquid-absorbent core 15 interposed between
the top- and backsheets 13, 14 and secured to the surfaces of these
top- and backsheets 13, 14 opposed to each other. The pad P
constructed in this manner is attached to the inner surface of the
nonwoven fabric layer m1 in the crotch region 3 of the article 1A
by means of an adhesive 16 applied to the outer surface of the
backsheet 14. The top- and backsheets 13, 14 are overlaid and
secured to each other along marginal zones extending outward beyond
a peripheral edge of the core 15.
FIGS. 5 and 6 are perspective views showing the article 1A as put
on the wearer's body. In FIG. 6, the wearer is illustrated as lying
face up.
To wear the article 1A, the lateral zones 7b in the rear waist
region 4 may be moved toward the lateral zones 7a in the front
waist region 2, then placed upon the outer side of the respective
lateral zones 7a and thereafter the loop members 12 may be engaged
with the respective hook members 11 so as to connect the front and
rear waist regions 2, 4 to each other. Upon connection of the front
and rear waist regions 2, 4 in this manner, the article 1A defines
a waist-hole 17 and a pair of leg-holes 18.
The first stretchable zone 8 lying in the lateral zones 7a of the
front waist region 2 and the second stretchable zone 9 lying in the
lateral zones 7b of the rear waist region 4 are substantially
connected to each other so as to form an annular configuration as
the loop members 12 come in engagement with the hook members 11.
The first and second stretchable zones 8, 9 cooperate to form the
annular configuration extending from a wearer's inguinal region
toward a wearer's waist region as the article 1A is put on the
wearer's body. In this way, the contractile force of these
stretchable zones 8, 9 is effective to tighten the wearer's
inguinal and waist regions in a thigh-surrounding direction
indicated by an arrow Y1.
The first and second stretchable zones 8, 9 are contractible also
in the longitudinal, i.e., a vertical direction indicated by an
arrow Y2 so that the contractile force of these elastic zones 8, 9
in the longitudinal direction functions to pull the crotch region 3
of the article 1A upward. With consequence, it is possible for the
article 1A to keep the crotch region 3 in close contact with a
wearer's crotch region and therefore to keep the pad P attached to
the crotch region 3 also in close contact with the wearer's crotch
region.
The lateral zones 7 of the article 1A are defined by the third
stretchable zones 10b having a stretch stress lower than in the
first and second stretchable zones 8, 9. Wearer's thighs are
surrounded with the third stretchable zones 10b in the
thigh-surrounding direction indicated by an arrow Y3. Thus these
third stretchable zones 10b serve, during use of the article 1A, to
prevent the anxiety that the first and second stretchable zones 8,
9 might restrict free movement of the wearer's legs. The front and
rear end zones 5, 6 of the article 1A defined by the third
stretchable zones 10a tighten the wearer's waist region in a
waist-surrounding direction indicated by the arrow X1 and thereby
prevent the article 1A from unintentionally slipping down along the
wearer's waist region.
The loop members 12 must be engaged with the hook members 11 to put
the article 1A on the wearer's body and such engagement between
these members 11, 12 necessarily results in connection between the
first stretchable zone 8 and the second stretchable zone 9. In
other words, it is impossible to bring the loop members 12 attached
to the lateral zones 7b in the rear waist region 4 in engagement
with any members or zones other than the hook members 11, for
example, with the nonwoven fabric layer m1 in the front waist
region 2 when it is intentioned to put the article 1A on the
wearer's body. It is thus ensured that the lateral zones 7a of the
front waist region 2 are connected to the lateral zones 7b of the
rear waist region 4 always at the proper positions thereof.
The positions at which the hook members 11 and the loop members 12
are attached to the lateral zones 7a of the front waist region 2
and to the lateral zones 7b of the rear waist region 4,
respectively, may be selectively changed as long as the hook
members 11 are provided to the first stretchable zone 8 and the
loop members 12 are provided to the second stretchable zone 9. The
positions at which the lateral zones 7a of the front waist region 2
and the lateral zones 7b of the rear waist region 4 are connected
to each other are adjusted accordingly.
The first and second stretchable zones 8, 9 exhibit a stretch
stress in a range of 0.25 30N when a width of the zones 8, 9 is 15
mm and the zones 8, 9 are stretched by 15% and a stretch stress in
a range of 0.6 50N when a width of the zones 8, 9 is 15 mm and the
zones 8, 9 are stretched by 40%. The third stretchable zones 10a,
10b exhibit a stretch stress in a range of 0.17 20N when a width of
the zones 10a, 10b is 15 mm and the zones 10a, 10b are stretched by
15% and a stretch stress in a range of 0.4 33N when a width of the
zones 10a, 10b is 15 mm and the zones 10a, 10b are stretched by
40%.
If the first and second stretchable zones 8, 9 exhibit a stretch
stress less than 0.25N when stretched by 15% or less than 0.6N when
stretched by 40%, the contractile force of the first and second
stretchable zones 8, 9 will be insufficient not only to bring the
crotch region 3 of the article 1A in close contact with the
wearer's crotch but also to ensure that the first and second
stretchable zones 8, 9 properly tighten the inguinal region and the
waist of the wearer. If the first and second stretchable zones 8, 9
exhibit a stretch stress exceeding 30N when stretched by 15% or
exceeding 50N when stretched by 40%, the contractile force of the
first and second stretchable zones 8, 9 in the longitudinal
direction will intend to slip the article 1A down along the
wearer's waist and raise an apprehension that the article 1A might
be unintentionally slip down off from the proper position. In
addition, the first and second stretchable zones 8, 9 will
excessively tighten the wearer's inguinal region and waist and the
wearer will create a feeling of discomfort against the wearer
during use of the article 1A.
If the third stretchable zones 10a, 10b exhibit a stretch stress
less than 0.17N when stretched by 15% or a stretch stress less than
0.4N when stretched by 40%, the contractile force of the third
stretchable zones 10a in the transverse direction will be
excessively low in compared to the contractile force of the first
and second stretchable zones 8, 9 in the longitudinal direction. As
a result, the article 1A may sometimes unintentionally slip down
off from its proper position during use thereof. If the third
stretchable zones 10a, 10b exhibit a stretch stress exceeding 20N
when stretched by 15% or a stretch stress exceeding 33N when
stretched by 40%, the contractile force of the first and second
stretchable zones 8, 9 in the longitudinal direction will be
restrained by the contractile force of the third stretchable zones
10a in the transverse direction depending on the stretch stress of
the first and second stretchable zones 8, 9. Consequently, the
expected function of these stretchable zones 8, 9 to keep the
crotch region 3 of the article 1A in close contact with the
wearer's crotch may be deteriorated.
It is possible to attach loop members to the first stretchable zone
8 in the lateral zones 7a of the front waist region 2 and to attach
hook members to the second stretchable zone 9 in the lateral zones
7b of the rear waist region 4. It is also possible to coat the
second stretchable zone 9 in the lateral zones 7b of the rear waist
region 4 with self-adhesives and to provide on the first
stretchable zone 8 in the lateral zones 7a of the front waist
region 2 with films attached thereto so as to be releasably
attached to the adhesives.
FIG. 7 is a partially cutaway plan view showing another example 1B
of the disposable wearing article, FIG. 8 is a sectional view taken
along a line D--D in FIG. 7, FIG. 9 is a sectional view taken along
a line E--E in FIG. 7 and FIG. 10 is a sectional view taken along a
line F--F in FIG. 7. In FIG. 7, a transverse direction is indicated
by an arrow X and a longitudinal direction is indicated by an arrow
Y.
An article 1B is composed of a front waist region 2, a rear waist
region 4 and a crotch region 3 extending between these two waist
regions 2, 4 and has front and rear end zones 5, 6 extending in the
transverse direction and lateral zones 7 extending in the
longitudinal direction. In the crotch region 3, the lateral zones 7
curve inward transversely of the article 1B so as to describe
circular arcs. The article 1B is provided on its surface facing the
wearer's body with an absorbent pad P releasably attached thereto
and this pad P comprises an absorbent core 15 interposed between a
liquid-pervious topsheet 13 and a liquid-impervious backsheet
14.
The article 1B comprises elastically stretchable fibrous nonwoven
fabric layers m1, m2 placed upon each other. These nonwoven fabric
layers m1, m2 are elastically stretchable in the transverse
direction as well as in the longitudinal direction not only in the
front and rear waist regions 2, 4 but also in the crotch region 3.
The article 1B is thus elastically stretchable in the transverse
direction as well as in the longitudinal direction in all regions,
i.e., in the front and rear waist regions 2, 4 and in the crotch
region 3. In the article 1B, the surfaces of these nonwoven fabric
layers m1, m2 opposed to each other are joined together
intermittently. The article 1B has a first stretchable zone 8, a
second stretchable zone 9 and third stretchable zones 10a, 10b
defined by the remaining regions with respect to those first and
second stretchable zones 8, 9.
The first stretchable zone 8 is bifurcated in a transverse middle
3a of the crotch region 3 so as to extend from the transverse
middle 3a to lateral zones 7a in the vicinity of the front end zone
5. The second stretchable zone 9 also is bifurcated in the
transverse middle 3a of the crotch region 3 so as to extend from
the transverse middle 3a to lateral zones 7b in the vicinity of the
crotch region 3. In the transverse middle 3a of the crotch region
3, the first stretchable zone 8 and the second stretchable zone 9
are contiguous to each other and extend in the longitudinal
direction. These first and second stretchable zones 8, 9 extend
around the crotch region 3 substantially in X-shape.
The third stretchable zones 10a lie outside the first and second
stretchable zones 8, 9 as viewed in the longitudinal direction and
define the front and rear end zones 5, 6 of the article 1B. The
third stretchable zones 10b lie outside of the first and second
stretchable zones 8, 9 as viewed in the transverse direction and
define the lateral zones 7 of the article 1A.
In the first and second stretchable zones 8, 9, a stretchable
fibrous nonwoven fabric layer m3 is interposed between the nonwoven
fabric layers m1, m2. The nonwoven fabric layer m3 also is
elastically stretchable in the transverse direction as well as in
the longitudinal direction and intermittently joined to the
surfaces of the nonwoven fabric layers m1, m2 opposed to each
other. These nonwoven fabric layers m1, m2, m3 are intermittently
joined one to another under no tension. Thus the first and second
stretchable zones 8, 9 respectively comprise those three fibrous
nonwoven fabric layers m1, m2, m3 placed one upon another. The
third stretchable zones 10a, 10b, on the other hand, respectively
comprise those two fibrous nonwoven fabric layers m1, m2.
Consequently, the basis weight of the nonwoven fabric layer is
higher in the first and second stretchable zones 8, 9 than in the
third stretchable zones 10a, 10b and the stretch stress is higher
in the stretchable zones 8, 9 than in the third stretchable zones
10a, 10b.
The lateral zones 7a in the front waist region 2 are provided with
first hook members 11 and second loop members 19. The hook members
11 are secured to an outer surface of the nonwoven fabric layer m2
in the first stretchable zone 8. The loop members 19 lie in the
third stretchable zones 10a placed aside from the first stretchable
zone 8 toward the front end zone 5 and secured to the outer surface
of the nonwoven fabric layer m2.
The lateral zones 7b in the rear waist region 4 are provided with
first loop members 12 and second hook members 20. The loop members
12 are secured to an inner surface of the nonwoven fabric layer m1
in the second stretchable zone 9. The hook members 20 lie in the
third stretchable zones 10a placed aside from the second
stretchable zone 9 toward the rear end zone 6 and secured to the
inner surface of the nonwoven fabric layer m1.
FIG. 11 is a perspective views showing the article 1B. To wear the
article 1B, the lateral zones 7b in the rear waist region 4 may be
moved toward the lateral zones 7a in the front waist region 2, then
placed upon the outer side of the respective lateral zones 7a and
thereafter the loop members 12 may be engaged with the respective
hook members 11 so as to connect the front and rear waist regions
2, 4 to each other.
Upon engagement of the loop members 12 with the respective hook
members 11, the first stretchable zone 8 lying in the lateral zones
7a of the front waist region 2 and the second stretchable zone 9
lying in the lateral zones 7b of the rear waist region 4 are
substantially connected to each other so as to form an annular
configuration. The first and second stretchable zones 8, 9
cooperate to form an annular configuration extending from the
wearer's inguinal region toward the wearer's waist region as the
article 1B is put on the wearer's body. In this way, the
contractile force of these stretchable zones 8, 9 is effective to
tighten the wearer's inguinal and waist regions in the
thigh-surrounding direction indicated by an arrow Y1.
The first and second stretchable zones 8, 9 are contractible in the
longitudinal, i.e., the vertical direction indicated by an arrow Y2
so that the contractile force of these elastic zones 8, 9 in the
longitudinal direction functions to pull the crotch region 3 of the
article 1B upward. With consequence, it is possible for the article
1B to keep the crotch region 3 in close contact with a wearer's
crotch region and therefore to keep the pad P attached to the
crotch region 3 also in close contact with the wearer's crotch
region.
The lateral zones 7 of the article 1B are defined by the third
stretchable zones 10b having a stretch stress lower than in the
first and second stretchable zones 8, 9. Wearer's thighs are
surrounded with the third stretchable zones 10b in the
thigh-surrounding direction indicated by an arrow Y3.
The first loop members 12 must be engaged with the first hook
members 11 to put the article 1B on the wearer's body and such
engagement between these members 11, 12 necessarily results in
connection between the first stretchable zone 8 and the second
stretchable zone 9. In other words, it is impossible to bring the
first loop members 12 attached to the lateral zones 7b in the rear
waist region 4 in engagement with any members or zones other than
the first hook members 11, for example, with the nonwoven fabric
layer m1 in the front waist region 2 when it is intentioned to put
the article 1B on the wearer's body. It is thus ensured that the
lateral zones 7a of the front waist region 2 are connected to the
lateral zones 7b of the rear waist region 4 always at the proper
positions thereof. The positions at which the hook members 1 and
the loop members 12 are attached to the lateral zones 7a of the
front waist region 2 and to the lateral zones 7b of the rear waist
region 4, respectively, may be selectively changed. The positions
at which the lateral zones 7a of the front waist region 2 are
connected with the lateral zones 7b of the rear waist region 4 are
adjusted accordingly.
The second hook members 20 are placed upon the outer surfaces of
the second loop members 19 as the first loop members 12 are engaged
with the first hook members 11, so the second hook members 20 can
be reliably engaged with the second loop members 19. In the article
1B, the third stretchable zones 10a lying in the front and rear end
zones 5, 6 can be substantially connected to each other as the
second hook members 20 are engaged with the second loop members 29.
In this way, the front and rear end zones 5, 6 defined by these
third stretchable zones 10a tighten the wearer's waist region in
the waist-surrounding direction indicated by an arrow X1 and
thereby prevent the article 1B from unintentionally slipping down
along the wearer's waist.
A stretch stress exhibited by the first and second stretchable
zones 8, 9 when a width of the zones 8, 9 is 15 mm and the zones 8,
9 are stretched by 15% and when a width of the zones 8, 9 is 15 mm
and the zones 8, 9 are stretched by 40% are same as those in the
case of FIG. 1. A stretch stress exhibited by the third stretched
zones 10a, 10b when a width of the zones 10a, 10b is 15 mm and the
zones 10a, 10b are stretched by 15% and when a width of the zone is
10a, 10b is 15 mm and the zones 10a, 10b are stretched by 40% are
also same as those in the case of FIG. 1.
It is possible to attach the loop members 12 to the first
stretchable zone 8 in the lateral zones 7a of the front waist
region 2 and to attach the hook members 11 to the second
stretchable zone 9 in the lateral zones 7b of the rear waist region
4. It is also possible to attach the hook members 20 to the third
stretchable zones 10a placed aside from the first stretchable zone
8 toward the front end zone 5 and to attach the loop members 19 to
the third stretchable zones 10a placed aside from the second
stretchable zone 9 toward the rear end zone 6.
It is possible to attach one of a hook member and a loop member to
the first stretchable zone 8 in the lateral zones 7a of the front
waist region 2 and the third stretchable zones 10a placed aside
from the first stretchable zone 8 toward the front end zone 5 and
to attach the other one of the hook member and the loop member to
the second stretchable zone 9 in the lateral zones 7b of the rear
waist region 4 and the third stretchable zones 10a placed aside
from the second stretchable zone 9 toward the rear end zone 6, or
vice versa.
It is also possible to coat the second stretchable zone 9 in the
lateral zones 7b of the rear waist region 4 and the third
stretchable zones 10a placed aside from the second stretchable zone
9 toward the rear end zone 6 with an adhesive and to provide on the
first stretchable zone 8 in the lateral zones 7a of the front waist
region 2 and on the third stretchable zones 10a placed aside from
the first stretchable zone 8 toward the front end zone 5 with a
film attached thereto so as to be releasably attached to the
adhesive.
As a stock material for the elastically stretchable fibrous
nonwoven fabric layers m1, m2, m3, melt blown or spun bond fibrous
nonwoven fabric may be used. As component fibers constituting these
nonwoven fabric layers m1, m2, m3, stretchable fibers obtained by
melt spinning thermoplastic elastomer resin may be used.
It is possible to use, as a stock material for the nonwoven fabric
layers m1, m2, m3, a composite nonwoven fabric comprising an
elastically stretchable hydrophobic fibrous nonwoven fabric made of
thermoplastic elastomer resin fibers and a hydrophobic fibrous
nonwoven fabric made of crimped fibers, obtained by melt spinning
thermoplastic synthetic resin selected from the group consisting of
polypropylene, polyethylene and polyester which is placed upon at
least one surface of the elastically stretchable hydrophobic
fibrous nonwoven fabric. In the article 1A, 1B, the nonwoven fabric
layers m1, m2, m3 may be replaced by an elastically stretchable
liquid-impervious plastic film.
A stock material for the topsheet 13 may be selected from the group
including a hydrophilic fibrous nonwoven fabric, a hydrophobic
fibrous nonwoven fabric having a plurality of pores and
liquid-pervious plastic film having a plurality of fine pores. A
stock material for the backsheet 14 may be selected from the group
consisting a hydrophobic fibrous nonwoven fabric, a breathable
liquid-impervious plastic film, a composite nonwoven fabric
comprising two hydrophobic fibrous nonwoven fabric layers laminated
one upon another and a composite sheet comprising a hydrophobic
fibrous nonwoven fabric and a breathable liquid-impervious plastic
film laminated one upon another.
The nonwoven fabric used as a stock material for the top- and
backsheet 13, 14 may be selected from the group consisting of
products obtained by spun lace-, needle punch-, melt blown-,
thermal bond-, spun bond-, chemical bond- and air
through-processes. Component fibers constituting the nonwoven
fabric may be selected from the group consisting of polyolefin-,
polyester- and polyamide-based fibers and core-sheath or
side-by-side type conjugated fibers of polyethylene/polypropylene
or polyethylene/polyester.
The core 15 comprises a mixture of fluff pulp and super-absorbent
polymer particles or a mixture of fluff pulp, super-absorbent
polymer particles and thermoplastic synthetic resin fibers, in both
cases, compressed to a given thickness. Preferably, the core 15 is
entirely wrapped with a liquid-pervious sheet such as a tissue
paper or a hydrophilic fibrous nonwoven fabric in order to prevent
the core 15 from getting out of its proper shape and/or to avoid
falling off of the polymer particles from the core 15. The polymer
particles may be selected from the group consisting of a starch-,
cellulose- and synthetic polymer-based particles.
Joining of the nonwoven fabric layers m1, m2, m3 one to another,
joining of the top- and backsheets 13, 14 to each other and
securing of the core 15 to the top- and backsheets 13, 14 may be
achieved by use of welding means such as a heat sealing or a sonic
sealing.
The article 1A, 1B as has been described with reference to the
accompanying drawings is suitable as a diaper cover adapted to be
used together with the absorbent pad P attached to the inner
surface thereof.
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